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81.
大鼠胼胝体内神经肽Y免疫反应阳性纤维的发育 总被引:1,自引:0,他引:1
本实验用免疫组织化学ABC法研究了大鼠胼胝体内神经肽Y免疫反应阳性(NPY-IR)纤维的生后发育。结果发现,许多NPY-IR纤维在大鼠出生时便存在于胼胝体内。NPY-IR胼胝体纤维的密度在生后1周内继续逐渐增高,在第2周内达到最高峰。之后,NPY-IR胼胝体纤维的密度逐渐下降,至第3周末时接近成年时的水平,即仅有少量NPY-IR纤维存在于胼胝体内。这些结果提示在大鼠早期生后发育过程中许多NPY-IR胼胝体纤维是暂时性的,其作用可能与大脑皮质的机能发育有关。 相似文献
82.
Characterization of eight polymorphic microsatellite loci for the giant grouper (Epinephelus lanceolatus Bloch) 总被引:1,自引:0,他引:1
Eight polymorphic microsatellite loci were isolated and characterized using a small insert genomic DNA library for the giant grouper (Epinephelus lanceolatus Bloch, 1790), a commercially valuable marine fish in tropical waters. They showed polymorphism information content ranging from 0.177 to 0.775, allele numbers ranging from two to 10, effective allele numbers ranging from 1.227 to 5.012, and observed and expected heterozygosities from 0.2 to 0.733 and from 0.185 to 0.801, respectively, which we anticipate will be useful for population genetic studies of the giant grouper. 相似文献
83.
记述了中国同脉缟蝇亚属20个种团,其中17个种团,即异突同脉缟蝇种团H.(H.)abnormis group,双带同脉缟蝇种团H.(H.)bistriata group,短突同脉缟蝇种团H.(H.)brevis group,台湾同脉缟蝇种团H.(H.)formosae group,河南同脉缟蝇种团H.(H.)henanensis group,叉突同脉缟蝇种团H.(H.)laticosta group,李氏同脉缟蝇种团H.(H.)lii group,背斑同脉缟蝇种团H.(H.)notostigma group,美额同脉缟蝇种团H.(H.)ornatifrons group,多斑同脉缟蝇种团H.(H.)picta group,五斑同脉缟蝇种团H.(H.)quiquenotat group,单突同脉缟蝇种团H.(H.)singularis group,纹额同脉缟蝇种团H.(H.)striatifrons group,斑腿同脉缟蝇种团H.(H.)substigmata group,西藏同脉缟蝇种团H.(H.)tibetensis group,三尖同脉缟蝇种团H.(H.)trispina group,爪突同脉缟蝇种团日.(H.)unguiculata group为首次提出,并描述了2新种,平截同脉缟蝇H.(H.)trunciformis sp.nov.和长膜同脉缟蝇H.(H.)longinotata sp.nov.,提供了该亚属分种团检索表.所有观察标本均保存于中国农业大学昆虫标本馆. 相似文献
84.
Proteome analysis of up-regulated proteins in the rat spinal cord induced by transection injury 总被引:3,自引:0,他引:3
Ding Q Wu Z Guo Y Zhao C Jia Y Kong F Chen B Wang H Xiong S Que H Jing S Liu S 《Proteomics》2006,6(2):505-518
The inability of the CNS to regenerate in adult mammals propels us to reveal associated proteins involved in the injured CNS. In this paper, either thoracic laminectomy (as sham control) or thoracic spinal cord transection was performed on male adult rats. Five days after surgery, the whole spinal cord tissue was dissected and fractionated into water-soluble (dissolved in Tris buffer) and water-insoluble (dissolved in a solution containing chaotropes and surfactants) portions for 2-DE. Protein identification was performed by MS and further confirmed by Western blot. As a result, over 30 protein spots in the injured spinal cord were shown to be up-regulated no less than 1.5-fold. These identified proteins possibly play various roles during the injury and repair process and may be functionally categorized as several different groups, such as stress-responsive and metabolic changes, lipid and protein degeneration, neural survival and regeneration. In particular, over-expression of 11-zinc finger protein and glypican may be responsible for the inhibition of axonal growth and regeneration. Moreover, three unknown proteins with novel sequences were found to be up-regulated by spinal cord injury. Further characterization of these molecules may help us come closer to understanding the mechanisms that underlie the inability of the adult CNS to regenerate. 相似文献
85.
Ning Xu Yijie Dong Xinxin Cheng Qilin Yu Kefan Qian Jiwei Mao Chang Jia Xiaohui Ding Bing Zhang Yulu Chen Biao Zhang Laijun Xing Mingchun Li 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》2014
Iron bioavailability is crucial for mitochondrial metabolism and biosynthesis. Dysregulation of cellular iron homeostasis affects multiple aspects of mitochondrial physiology and cellular processes. However, the intracellular iron trafficking pathway in Candida albicans remains unclear. In this study, we characterized the Mrs4–Ccc1–Smf3 pathway, and demonstrated its important role in maintaining cellular iron levels. Double deletion of vacuolar iron exporter SMF3 and mitochondrial iron transporter MRS4 further elevated cellular iron levels in comparison with the single MRS4 deletion. However, deletion of vacuolar iron importer CCC1 in the mrs4?/? mutant restored cellular iron homeostasis to normal wild-type levels, and also normalized most of the defective phenotypes in response to various environmental stresses. Our results also suggested that both Mrs4 and Ccc1 contributed to the maintenance of mitochondrial function. The mrs4?/? and mrs4?/?smf3?/? mutants exhibited an obvious decrease in aconitase activities and mitochondrial membrane potential, whereas deletion of CCC1 in the mrs4?/? mutant effectively rescued these defects. Furthermore, we also found that the Mrs4–Ccc1–Smf3 pathway was indispensable for cell-wall stability, antifungal drug tolerance, filamentous growth and virulence, supporting the novel viewpoint that mitochondria might be the promising target for better antifungal therapies. Interestingly, the addition of exogenous iron failed to rescue the defects on non-fermentable carbon sources or hyphae-inducing medium, indicating that the defects in mitochondrial respiration and filamentous development might result from the disturbance of cellular iron homeostasis rather than environmental iron deprivation. Taken together, our results propose the Mrs4–Ccc1–Smf3 pathway as a potentially attractive target for antifungal drug development. 相似文献
86.
Hui‐Mei Wu Li‐Feng Zhang Pei‐Shang Ding Ya‐Jing Liu Xu Wu Jiang‐Ning Zhou 《Journal of cellular and molecular medicine》2014,18(7):1300-1312
The rational of neural stem cells (NSCs) in the therapy of neurological disease is either to replace dead neurons or to improve host neuronal survival, the latter of which has got less attention and the underlying mechanism is as yet little known. Using a transwell co‐culture system, we reported that, in organotypic brain slice cultures, NSCs significantly improved host neuronal viability. Interestingly, this beneficial effect of NSCs was abrogated by a microglial inhibitor minocycline, while it was mimicked by a microglial agonist, Toll‐like receptor 9 (TLR9) ligand CpG‐ODN, which supports the pro‐vital mediation by microglia on this NSCs‐improved neuronal survival. Moreover, we showed that NSCs significantly induced host microglial movement and higher expression of a microglial marker IBA‐1, the latter of which was positively correlated with TLR9 or extracellular‐regulated protein kinases 1/2 (ERK1/2) activation. Real‐time PCR revealed that NSCs inhibited the expression of pro‐inflammatory molecules, but significantly increased the expression of molecules associated with a neuroprotective phenotype such as CX3CR1, triggering receptor expressed on myeloid cells‐2 (TREM2) and insulin growth factor 1 (IGF‐1). Similarly, in the microglia cells, NSCs induced the same microglial response as that in the slices. Further treatment with TLR9 ligand CpG‐ODN, TLR9 inhibitor chloroquine (CQ) or ERK1/2 inhibitor U0126 demonstrated that TLR9‐ERK1/2 pathway was involved in the NSCs‐induced microglial activation. Collectively, this study indicated that NSCs improve host neuronal survival by switching microglia from a detrimental to a neuroprotective phenotype in adult mouse brain, and the microglial TLR9‐ERK1/2 pathway seems to participate in this NSCs‐mediated rescue action. 相似文献
87.
The influence of low frequency (50 Hz repetition rate) pulsed electromagnetic field (EMF) on PC12 cell neurite outgrowth in vitro was investigated in this study. We studied the percentage of neurite bearing cells, average length of neurites, and directivity of neurite outgrowth in PC12 cells cultured for 96 h in the presence of nerve growth factor (NGF). PC12 cells were exposed in one incubator to pulsed EMF at 1.36 mT (peak value) generated by a pair of Helmholtz coils, and the control samples were placed in another identical incubator. We found that the pulse duty cycle had significant effect on neurite outgrowth. Low (10%) pulse on-time significantly inhibited the percentage of neurite bearing cells, but at the same time increased the average length of neurites, while 100% on-time (DC) had exactly the opposite effects. Furthermore, we found that neurites were prone to extend along the direction of pulsed EMF with 10% pulse on-time. Our studies show that neurite outgrowth in PC12 cells is sensitive to the pulse duty and this sensitivity was associated with NGF concentration. 相似文献
88.
Qianhua Zhao Bin Zhou Ding Ding Satoshi Teramukai Qihao Guo Masanori Fukushima Zhen Hong 《PloS one》2014,9(4)
Objectives
Progressive cognitive decline is a characteristic hallmark of AD. It is important to identify prognostic markers to improve patient care and long-term planning. We aimed to identify the characteristics of disease progression in AD patients, focusing on cognitive decline and its related factors.Methods
Clinically diagnosed AD patients in a memory clinic were followed. The mini–mental state examination (MMSE) and a battery of other neuropsychological tests were performed to assess the rate of cognitive decline and to analyze the related factors.Results
A total of 165 AD patients were analyzed for cognitive changes. The MMSE scores declined at a rate of 1.52 points per year. Most neuropsychological test scores deteriorated significantly over time. Younger and early-onset AD patients deteriorated more rapidly than older and late-onset patients in global cognition and executive function. Men declined faster in memory but slower in attention than women. Higher education was associated with more rapid deterioration in visuo-spatial ability. Family history, hypertension and cerebral vascular disease were also associated with disease progression.Conclusion
Attention, executive and visuo-spatial functions deteriorate at faster rates than other cognitive functions in AD patients. Age and age at onset were the main factors that associated with deterioration. 相似文献89.
Dongmei H Jing L Mei X Ling Z Hongmin Y Zhidong W Li D Zikuan G Hengxiang W 《Cytotherapy》2011,13(8):913-917
Background aimsThe aims of this study were to observe the safety and effectiveness of umbilical cord mesenchymal stromal cells (UC-MSC) in the treatment of spinocerebellar ataxia (SCA) and multiple system atrophy-cerebellar type (MSA-C).MethodsFrom October 2009 to September 2010, 14 cases of SCA and 10 cases of MSA-C were given UC-MSC by weekly intrathecal injection, at a dose of 1 × 106/kg four times as one course. All the patients received one course of treatment, except three patients who received two courses. The movement ability and quality of daily life were evaluated with the International Cooperative Ataxia Rating Scale (ICARS) and Activity of Daily Living Scale (ADL) and the scores compared with those before cell therapy. A follow-up of 6–15 months was carried out for all of the patients.ResultsThe results showed that the ICARS and ADL scores were significantly decreased 1 month after treatment (P < 0.01). The symptoms, including unstable walking and standing, slow movement, fine motor disorders of the upper limbs, writing difficulties and dysarthria, were greatly improved except for one patient, who had no response. The observed side-effects included dizziness (four patients), back pain (two cases) and headache (one case), which disappeared within 1–3 days. During the follow-up, 10 cases remained stable for half a year or longer, while 14 cases had regressed to the status prior to the treatment within 1–14 months (an average of 3 months).ConclusionsIntrathecal injection of UC-MSC is safe and can delay the progression of neurologic deficits for SCA and MSA-C patients. 相似文献
90.
Chen SB Tan JH Ou TM Huang SL An LK Luo HB Li D Gu LQ Huang ZS 《Bioorganic & medicinal chemistry letters》2011,21(3):1004-1009
Discovery of potent and selective ligands for telomeric G-quadruplex DNA is a challenging work. Through a combination approach of pharmacophore model construction, model validation, database virtual screening, chemical synthesis and interaction evaluation, we discovered and confirmed triaryl-substituted imidazole TSIZ01 to be a new telomeric G-quadruplex ligand with potent binding and stabilizing activity to G-quadruplex DNA, as well as a 8.7-fold selectivity towards telomeric G-quadruplex DNA over duplex DNA. 相似文献